Sweep second watch movement

ABSTRACT

A driven wheel in a timing mechanism is provided with two coaxial, rotationally interdependent planet wheels, one of which drives a gear train for a sweep second hand as well as for minute and hour hands, the other planet wheel being engaged with a normally stationary gear which is selectively driven by a crown wheel positioned externally of the gear casing. The crown wheel is integral with an axially displaceable tube by means of which male and female members are engaged to enable the crown wheel to displace said normally stationary gear to set the minute and hour hands.

United States Patent 11 1 'Golay g July 24, 1973 [54] SWEEP SECOND WATCH MOVEMENT 3,499,280 3/1970 Erard 58/63 [7 5] Inventor: Jean-Pierre Golay, Tramelan,

' Switzerland Primary Examiner-George H. Miller, Jr. Attorney-Eric H. Waters et al. [73] Ass1gnee: Bernard Golay S.,A

[22] Filed: May 22, 1972 [57] ABSTRACT [2]] Appl 255464 A driven wheel in a timing mechanism is provided with two coaxial, rotationally interdependent planet wheels, [30] Foreign Application Priority Data one of which drives a gear train for a sweep second May 26 1971 Switzerland 7656/71 hahd as as minute and hands the planetwheel being engaged with a normally stationary 521 US. Cl 58/59, 58/63, 58185.5 which is seiwiveiy drive" by 3 Wheel P 51 1111. C1. G04b 33/00, 00415 27/02 timied of the gear casihe ciowhvwheei [58] Field of Search 58/7, 59, 63 85.5 is integral with axiaiiy disphihhahie tube by means g which male and female members are engaged to enable [56] Rderenccs Cited I the crown wheel to displace said normally stationary UNITED STATES PATENTS gear to set the minute and hour hands. 3,029,592 4/1962 Bandi 58/59 X 5 Claims, 1 Drawing Figure 5 V i/Vi 2 l II|-l //////////////////////////////////n SWEEP SECOND WATCH MOVEMENT FIELD OF THE INVENTION The present invention relates to sweep second watch movements.

SUMMARY OF THE INVENTION A characteristic of the invention is that a wheel called the fourth wheel driven by an escape pinion carries two coaxial planet wheels rotationally interdependent, one of these planet wheels engaging with a normally stationary gear and the other with a cannon pinion, the planet wheels thus formed and the works with which they cooperate being so proportioned that at each full 360 turning of the planet wheels, the cannon pinion moves through an angle of 6' in the same direction of rotation.

BRIEF DESCRIPTION OF THE DRAWING The invention of whichone embodiment is given by way of example, is illustrated in the attached drawing in which the sole FIGURE is a cross sectional view of the central portion of a movement embodying the invention.

DETAILED DESCRIPTION 7 Wheel 1 is the fourth wheel driven by the escape pinion 2.

Close to its periphery, it carries two coaxial planet wheels 3 and 4 which are rotationally interdependent and which it drives at the rate of one revolution per minute corresponding to the rotation of the sweep second.

. Planet wheel 3 of this pair engages with a wheel 5 which normally stands still, while the second planet .wheel 4 engages with the cannon pinion 6.

This latter in turn engages with the gear of minute wheel 7 whose pinion 8 drives the hour wheel 9.

The position of cannon pinion 6 is axially determined by a bearing 10 of a tube 11 mounted pivotably in a tube 12 which is drift-driven to the center of the movement; a r

. Gear 5 is held steady by,friction applied by bridge 13 by means of a flexible bolt or ring 14. The planet wheels 3 and.4 run interdependently with the fourth wheel 1 through a 360 arc each minute.

Due to the reduction gear provision between the said fourth wheel, the planet wheels and the cannon pinion 6, at each revolution of the planet wheels the cannon pinion 6 moves 6 in the same direction of rotation. The cannon pinion 6 governing the minute hand will move the same through one-sixtieth of a turn, namely ,1 minute.

This arrangement which is purely and simply a differential mechanism is extremely simple compared with known mechanisms having sweep second hands and, as is evident, it allows equally simplified means for setting thehour to be provided.

For this purpose, the wheel 5 with bridge 13, which is normally still, carries a butt 15 which allows it to work in conjunction with hour-setting means.

The hour-setting means are interdependently united with the base 16 of the gear case and include a crown wheel tube 17, the hour-setting crown wheel 18 and a flexible rim 19 working in conjunction with two axially spaced circular grooves therein so as to fix two posi tions of axial rest and hour-set. These various components are coaxial with the fourth wheel 1.

Means for leakproofing the said crown wheel are provided by element 20, therebeing provided a rim 21 having a square inside aperture and drift-driven into the tube of the crown wheel.

Said aperture works in conjunction with a bushing 22 allowing the crown wheel 18 to be coupled in rotation with the butt 15, since the said bushing exhibits an equivalent square aperture. Said bushing moves for that purpose, axially with the crown wheel, with however the interposing of a resilient component 23.

In the idle position shown in the drawing, the crown wheel 18 is inoperative. Exertion of axial traction of the crown wheel compresses the flexible unit 23, the rim 19 moving into position in a lower notch of the crown wheel 18.

At that instant, either the butt of bushing 22 occupies an angular position such as to couple with the butt 15, or a position antagonistic to coupling of these two components which are of mating male and female section. In that case the connection will be effected after a setting of the crown wheel into rotation.

Inany case, it will become possible to drive the butt 15 in rotation by means of the crown wheel 18 and therefore to make the normally stationary gear 5 turn around.

It is then clear that the fourth wheel 1 will come to a standstill and the effect of such handling will be to set the planet wheels 3 and 4 rotating, which will cause an angular displacement of these latter and of the cannon pinion 6 in desired direction. Hence the minute hand will be moved and, through the minute train, the hour hand will be moved. The setting of the hour hand is thus effected.

This arrangement has the advantage of allowing a setting of the hour hand through the base by means of a crown wheel occupying the center of the movement, which in particular facilitates the mounting of a watertight case base. This also results in a saving of space as compared with all known types of mechanisms.

What is claimed is:

l. A watch movement comprising a normally stationary gear, a driven wheel, two coaxial and rotationally interdependent planet gears carried by said driven wheel and rotating about the periphery of said normally stationary gear, minute and hour hand means, a cannon pinion for driving said minute and hour hand means being connected to said planet gears, said planet gears being so arranged that for each 360 revolution thereof said cannon pinion rotates 6 in the same direction of rotation, a crown wheel, and means selectively coupling said crown wheel with said normally stationary gear to rotate the latter and operate the cannon pinion through said planet gears so as to adjust the relative setting of said minute and hour hand means.

2. A movement as claimed in claim 1 comprising means frictionally engaging the first said gear to maintain the same normally stationary.

3. A movement as claimed in claim 1 wherein said selective coupling means include mating male and female parts.

4. A movement as claimed in claim 1 wherein said crown wheel includes a tubular extension provided with spaced annular notches, comprising a flexible member adapted for selectively engaging in one of said notches.

5. A movement as claimed in claim 4 comprising further means housing said flexible member and a watertight means between said further means and extension. =8 i I! 

1. A watch movement comprising a normally stationary gear, a driven wheel, two coaxial and rotationally interdependent planet gears carried by said driven wheel and rotating about the periphery of said normally stationary gear, minute and hour hand means, a cannon pinion for driving said minute and hour hand means being connected to said planet gears, said planet gears being so arranged that for each 360* revolution thereof said cannon pinion rotates 6* in the same direction of rotation, a crown wheel, and means selectively coupling said crown wheel with said normally stationary gear to rotate the latter and operate the cannon pinion through said planet gears so as to adjust the relative setting of said minute and hour hand means.
 2. A movement as claimed in claim 1 comprising means frictionally engaging the first said gear to maintain the same normally stationary.
 3. A movement as claimed in claim 1 wherein said selective coupling means include mating male and female parts.
 4. A movement as claimed in claim 1 wherein said crown wheel includes a tubular extension provided with spaced annular notches, comprising a flexible member adapted for selectively engaging in one of said notches.
 5. A movement as claimed in claim 4 comprising further means housing said flexible member and a watertight means between said further means and extension. 